Wireless communication systems are widely deployed to provide various types of communication content such as voice, data, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, 3GPP Long Term Evolution (LTE) systems, and orthogonal frequency division multiple access (OFDMA) systems.
Generally, a wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals. Each terminal (also referred to as a user equipment or “UE”) communicates with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. This communication link may be established via a single-in-single-out, multiple-in-signal-out or a multiple-in-multiple-out (MIMO) system.
Some systems may utilize carrier aggregation, whereby multiple carriers are used to increase available bandwidth resources. Each aggregated carrier is referred to as a component carrier, CC. Often a primary component carrier (PCC) is used for various communications (e.g., control and user data in a primary cell or “PCELL”), while other secondary component carriers (SCCs) are limited to certain types of communication (e.g., only user data in a secondary cell or “SCELL”).
In devices utilizing multiple antennas, algorithms exist for switching between antennas in an effort to achieve optimum performance (e.g., to switch from using a certain antenna that is blocked by how the device is being held). The switching may be based on reference signal receive power (RSRP) measurements obtained on the different antennas.
Unfortunately, such switching algorithms have been designed mainly for single-cell (single component carrier) scenarios, which presents drawbacks in carrier aggregation scenarios. For example, a UE with more than one serving cell (a PCELL and at least one SCELL) may use a switching algorithm that triggers a switch solely based on measurements made on a PCELL even to switch the antennas for the SCELL. Thus, the SCELL blindly follows the switching decision made for the PCELL.